Full page screenshot in One Click

manifest.json

{
  "update_url": "https://clients2.google.com/service/update2/crx",
  "manifest_version": 3,
  "name": "Full page screenshot in One Click",
  "version": "1.0",
  "default_locale": "en",
  "description": "A screenshot of the full page in one click. Just click one button and the screenshot will be saved on your computer.",
  "permissions": [
    "scripting",
    "activeTab"
  ],
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "html2canvas.min.js"
      ],
      "run_at": "document_end"
    }
  ],
  "background": {},
  "action": {
    "default_popup": "popup.html",
    "default_icon": {
      "16": "icons/16.png",
      "48": "icons/48.png",
      "128": "icons/128.png"
    }
  },
  "icons": {
    "16": "icons/16.png",
    "48": "icons/48.png",
    "128": "icons/128.png"
  }
}